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131.
Thirteen basidiospore-derived isolates of Pleurotus ostreatus f6 strain differing in the level of ligninolytic enzyme production and other characteristics (mycelium extension rate, colony morphology) from the parental strain were cultivated on natural substrates. Under these conditions ligninolytic enzyme activity, loss of organic mass, polycyclic aromatic hydrocarbons (PAHs) degradation and colonization of sterile and nonsterile soil were studied. The activity of ligninolytic enzymes was substantially higher in straw than in liquid culture, although the differences between the isolates were less pronounced on this substrate. Some of the isolates showed a very good ability to decompose the lignocellulosic substrate (straw) and a relatively high loss of organic mass was found after 50 days of cultivation in these strains. The original strain f6 and isolates B13 and B26 successfully degraded all seven tested PAH compounds present in experimental soil samples, but the higher or lower ligninolytic enzyme production of isolates tested had no substantial effect on the extent of the degradation. In our screening, six basidiospore-derivedisolates growing well in nonsterile soil were found, whichcould be suitable for the prospective biotechnological exploitation.  相似文献   
132.
污染土壤中多环芳烃生物降解的调控研究   总被引:23,自引:6,他引:17  
选用温度、湿度、表面活性剂TW80和CNP比4个因素为调控因子,采用正交法进行周期为150天的实验研究.结果表明,30天后,土壤中PAHs的降解率可达44.5~74.6%,60天后,达70.4~93.7%,降解率的不同与调控条件显著相关.在此期间,降解最佳条件为40℃,湿度25%,CNP比为120101,TW80分别为200~500mg·kg-1.实验结束时,土壤中PAHs的降解率达91.2~99.8%.降解的最佳条件是40℃,湿度15%.经R值判别表明,不同时期各因子对PAHs降解影响有所不同.温度对PAHs降解影响较大,表面活性剂对土壤中PAHs的生物降解有调控作用.  相似文献   
133.
Summary Cultures ofMinthostachys mollis were established from nodal explants obtained under aseptic conditions. Explants were cultured on Murashige and Skoog (MS) half-strength medium containing 6-benzyladenine (BA), and/or naphthaleneacetic acid (NAA). Optimum numbers of healthy shoots were induced on media containing 0.05 μM NAA plus 2.2 μM BA; higher concentrations caused more hyperhydricity and less extension. Rooting was achieved on half-strength MS medium with 0.05 μM NAA. Plantlets were acclimatized and successfully transferred to soil. Essential oil composition of the regenerated plants were determined by gas chromatography/mass spectrometry and little differences were found in the essential oil composition with the plant grown in the wild.  相似文献   
134.
From the stem bark of Zanthoxylum thomense a new amide, zanthomamide has been isolated and characterized as N-methyl, N-cinnamyl-(3′,4′-methylenedioxy)-phenylethylamine. Other constituents identified are the known benzophenanthridines, decarine, norchelerythrine and angoline.  相似文献   
135.
The sediment quality triad (SQT) assumes that three measurements (sediment chemistry, laboratory bioassay, and benthic macroinvertebrate counts) comprise an independent assessment of impact, which when integrated using a weight-of-evidence approach provides a comprehensive assessment of risk. An SQT assessment was conducted on 41 sediment samples collected adjacent to a manufactured gas plant site on the freshwater reach of the Hudson River in New York State. The assessment shows that the benthic macroinvertebrate data did not correlate with either sediment or pore water polycyclic aromatic hydrocarbon (PAH) concentrations, nor did these data show consistent relationships to the results of laboratory bioassay testing (Hyalella azteca 28-day survival or biomass). The benthic community across the site and reference areas was comprised of few taxa, all of which were pollution-tolerant organisms with tolerance values greater than or equal to five. Only in significantly impacted sediment samples with PAH concentrations in the thousands of milligrams per kilogram, pore water concentrations above 100 toxic units, and visible non-aqueous phase liquid present in the sample did the benthic macroinvertebrate data show a response. In contrast, sediment and pore water PAH measurements and H. azteca toxicity testing provided consistent interpretation of impact. These results illustrate that benthic macroinvertebrate data may contain less information value and be a more challenging line of evidence to interpret in triad studies conducted in certain ecological settings; in this case, a large-order river with a relatively depauperate benthic community dominated by species tolerant of PAHs.  相似文献   
136.
不同温度条件下香水文心兰花香气的成分分析及感官评定   总被引:1,自引:0,他引:1  
Flower aromatic components and their relative contents of Oncidium Sharry Baby ‘Sweet Fragrance ’ at full flowering stage under conditions of 10 ℃, 20 ℃ and 30 ℃ were analyzed by solid phase micro-extr...  相似文献   
137.
138.
Adducts of benzo[a]pyrene-diolepoxide (BPDE) with blood nucleophiles have been used as biomarkers of exposure to polycyclic aromatic hydrocarbons (PAHs). The most popular such assay is a competitive enzyme-linked immunosorbent assay (ELISA) that employs monoclonal antibody 8E11 to detect benzo[a]pyrene tetrols following hydrolysis of BPDE adducts from lymphocyte DNA or human serum albumin (HSA). Here we used 8E11 as the capture antibody in a sandwich ELISA to detect BPDE-HSA adducts directly in 1-mg samples of HSA or 20 μl of serum/plasma. The assay employs an anti-HSA antibody for detection, and this is amplified by an avidin/biotinylated horseradish peroxidase complex. The sandwich ELISA has advantages of specificity and simplicity and is approximately 10 times more sensitive than the competitive ELISA. To validate the assay, HSA samples were assayed from three populations with known high PAH exposures (coke oven workers), medium PAH exposures (steel factory control workers), and low PAH exposures (volunteer subjects) (n = 30). The respective geometric mean levels of BPDE-HSA adducts—67.8, 14.7, and 1.93 ng/mg HSA (1010, 220, and 28.9 fmol BPDE equiv/mg HSA)—were significantly different (P < 0.05). The sandwich ELISA will be useful for screening PAH exposures in large epidemiologic studies and can be extended to other adducts for which capture antibodies are available.  相似文献   
139.
The components of biological membranes are present in a physical mixture. The nonrandom ways that the molecules of lipids and proteins mix together can strongly influence the association of proteins with each other, and the chemical reactions that occur in the membrane, or that are mediated by the membrane. A particular type of nonrandom mixing is the separation of compositionally distinct phases. Any such phase separation would result in preferential partition of some proteins and lipids between the coexisting phases, and thus would influence which proteins could be in contact, and whether a protein could find its target. Phase separation in a plasma membrane would also influence the binding of molecules from outside the cell to the membrane, including recognition proteins on viruses, bacteria, and other cells. The concept of these and other events associated with membrane phase separation are sometimes grouped together as the “raft model” of biological membranes. Several types of experiments are aimed at detecting and characterizing membrane phase separation. Visualizing phase separation has special value, both because the immiscibility is so decisively determined, and also because the type of phase can often be identified. The fluorescence microscope has proven uniquely useful for yielding images of separated phases, both in certain cell preparations, and especially in models of cell membranes. Here we discuss ways to prepare useful model membranes for image studies, and how to avoid some of the artifacts that can plague these studies.  相似文献   
140.
人乳头瘤病毒(Human Papillomavirus HPV)感染是导致性传播疾病的常见原因,上世纪八十年代初,首次报道生殖器HPV感染与宫颈癌之间的联系,认为HPV感染是95%以上宫颈癌变的高危因素。随着分子生物学技术的发展,对HPV致癌机制的研究不断深入,取得大量有价值的成果,现就HPV的致癌途径与协同因素探讨宫颈癌的发病机制以及对HPV检测方法等方面的研究进行综述。  相似文献   
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